|Transmission System for Digital Terrestrial Television Broadcast
Overview of the ARIB Standard (ARIB STD-B31)
This ARIB standard is intended to stipulate a transmission system pertaining to digital terrestrial television broadcast of the standard television broadcast and the like carried out by broadcast stations, and applies to digital terrestrial television broadcast that uses a frequency in the UHF and VHF bands.
Note that for the standards of the information source coding scheme, multiplexing scheme, and the like among standards related to digital terrestrial television broadcast, readers should refer to the separately provided ARIB standards.
Further, guidelines for the conditions related to the recommended program transmission and transmission equipment in actual operations are provided in appended documents, and concrete examples of techniques related to the basic underlying technology are provided as a reference.
1. Scope (version 1.0)
Transmission system for digital terrestrial television broadcast that uses a frequency in the UHF and VHF bands
This standard is composed of three sections: the body of the standard, "Transmission system for digital terrestrial television broadcast, "Appendix: Operating guidelines for digital terrestrial television broadcast," and "References."
An overview of each section is given below.
(1) Transmission system for digital terrestrial television broadcast
Chapter 1: General
Describes the objective, applications, reference documents, related documents, terms, and abbreviations
Chapter 2: Overview of the ISDB-T System
Provides an overview of the features of the ISDB-T system, the digital terrestrial television broadcasting system used in Japan
Chapter 3: Channel Coding Scheme
Stipulates multiple frames, error correction, energy dispersal, delay compensation, and other basic elements of the channel coding scheme in the ISDB-T system
Chapter 4: Frequency Conditions
Stipulates the frequency bandwidth, allowable deviation, transmission spectral mask, and the like that are used in digital terrestrial television broadcast
(2) Appendix: Operating guidelines for digital terrestrial television broadcast
The appendix describes as guidelines several conditions of the recommended program transmission and the transmission equipment for actual broadcast.
- Arrangement of the transmission spectrum
Center frequency carrier for each mode, relationship between TV channel and OFDM carrier, etc.
- Operating guidelines for hierarchical transmission
a) Spectral composition of hierarchical transmission, a means of sending multiple signals, PAT, NIT, and CAT, a means of sending PCR in a partially received layer, etc.
b) Channel coding scheme for hierarchical transmission: Hierarchical division/synthesis and clock, details of serial/parallel processing
- Operating guidelines for synchronization
Three conditions necessary for operating SFN ? transmission frequency, IFFT sampling frequency, and agreement of transmitted waveform ? and others
The reference materials concern the following subjects that may be conducive to the future construction of transmission equipment and networks for digital broadcast.
- Illustrating the amount of transmission/reception delay resulting from various forms of interleaving at the channel-coding unit
- Illustrating a system that can handle low-rate sound and the transmission of control data as a test case of an AC transmission system
- Developing solutions for the execution of line design as important things in the construction of a broadcast wave network. This is a test case that was carried out based on the Fiscal 1999 Report of the Frequency Planning Technical Committee of the Telecommunication Technology Council, in which a network, from the studio to the receiver, is modeled after the existing network.
3. Overview of the system and conceptual illustration of service
|Overview of the digital terrestrial television broadcast system
||MPEG-2 Audio AAC
||BML (multimedia coding scheme based on XML)
||Outer code (Reed-Solomon code) + inner code (convolution code)
||OFDM ?DQPSK, QPSK, 16QAM, 64QAM?
(Maximum value when 64QAM is used for the modulation scheme)
Conceptual illustration of service